The present invention relates to a corneal surgical apparatus for incising a cornea in a flap shape.
As corneal refractive surgery, there has been widely adopted the LASIK (laser assisted in situ keratomileusis) method, in which a flap is formed by incising a portion ranging from a corneal epithelium to a corneal stroma, the corneal stroma is ablated by opening the flap and irradiating it with a laser beam, and the flap is returned (closed) to the initial state. In recent years, however, there has been proposed a new method called the Epi-LASIK (Epithelial LASIK), in which a flap (as will be called a “corneal epithelium flap”) is formed by incising and peeling only a portion of the corneal epithelium and then the corneal stroma is ablated by irradiating it with the laser beam. The corneal surgical apparatus for the Epi-LASIK for preparing the corneal epithelium flap is also proposed. In this apparatus, the corneal epithelium flap is prepared by moving (forward) a blade, which is being oscillated at a high speed in an edge width direction of the blade, in a peeling (incising) direction of the corneal epithelium to a predetermined position. After the corneal epithelium flap is prepared, the blade is moved (backward) in the direction backward of the peeling direction to the initial position.
In the aforementioned apparatus for the Epi-LASIK, some is equipped with a cornea applanater for applanating the cornea substantially flatly prior to the blade to be moved forward, but another is not. The former is advantageous in that it can peel the corneal epithelium uniformly, but has a problem that the corneal epithelium flap may be broken or extended by the friction with the cornea applanater when the blade is moved backward to the initial position after the flap was prepared. On the other hand, the latter does not have the same problem, but has another problem that the corneal epithelium may not be uniformly peeled off.